On 11/11/2014 03:43 PM, Trond Myklebust wrote: > On Tue, Nov 11, 2014 at 2:16 PM, Steve Dickson <SteveD@xxxxxxxxxx> wrote: >> >> >> On 11/11/2014 10:01 AM, Trond Myklebust wrote: >>> One thing you should note when doing this: the current parser for >>> /etc/nfsmount.conf does not support minor versions. I think it needs >>> to, so that we can continue to use it to set defaults. >> Well setting Nfsvers=4.1 will give you a v4.1 mounts (assuming >> the server supports v4.1. but setting Defaultvers=4.1 does >> give you a v4.0 mount, which will need to be fixed. >> >>> >>> ...and to answer your questions above, I think that we should be able >>> to specify a 'default nfsv4 minor version' in /etc/nfsmount.conf, and >>> then negotiate down from there. >>> IOW: extend the 'Defaultvers' and 'Nfsvers' options to support 4.0, >>> 4.1, 4.2,.... >> Well Defaultvers is a negotiation with the server, Nfsvers is not. >> So when Nfsvers set set there is no negotiation, they get what is >> set to (aka 3, 4, 4.0, 4.1, just like the command line). >> >> With Defaultvers its a negotiation so set it to highest >> version and let it go... I'm not sure we need another >> variable to complicate things... >> >>> >>> The result should be that If I do 'mount -t nfs' with no '-overs' >>> option, then we start at 4.1 (if that is the default in >>> /etc/nfsmount.conf) and then try 4.0, 3, 2 in that order. >>> If I do 'mount -t nfs -overs=4', then again consult /etc/nfsmount.conf; >>> - if there is a default matching a v4 minor version, then start at >>> that and negotiate down (but stop at 4.0). >> Again, I'm thinking this type of complexity is not needed (especially >> from a testing matrix point of view). >> >> besides, if someone is specifying a version on the command line, is most likely >> they are not going to be using /etc/nfsmount.conf as all... >> >>> - if there is no default in /etc/nfsmount.conf, then perhaps assume a >>> default of 0(????) >> I'm thinking why not default to the better minor version?? 4.1 => 4.0 => 3 > > So at which minor version do you start? 4.10, 4.100?... The highest one.... Set Defaultvers to the highest version (including minor version) and then let the negotiations happen. > We don't want to have to recompile mount every time we add a new minor > version in order to bump the maximum number, which is why I think we > want to use /etc/nfsmount.conf and Defaultvers to define that (and > assume '0' if undefined). I agree. The fact that you can't set DefaultVers=4.2 and then negotiated down to what both sides support (even if its v3) is a problem and needs to be fixed. My point is I don't think we need another variable, say DefaultMinVers, that defines the minor version of v4. I'm thinking that's its overkill and adds unnecessary complexity. steved. -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
